Alcohol abuse is a major health problem in the US. This is especially true among certain populations, such as those affected by MV infection. Previous studies demonstrated that ethanol use among HIV infected homosexual and bisexual men is significantly more common than those not infected. As the HIV epidemic in this country evolves, HIV is increasingly affecting populations who abuse a number of substances, including alcohol. Ethanol consumption is known to alter host immunity and suppress host defenses to a number of infectious agents. Many of these infectious diseases are amenable to prevention through vaccination. Surprisingly, the impact of acute and chronic ethanol consumption on the ability of vaccines to alter host immunity has not been systematically studied. Infections due to cytomegalovirus (CMV) are common worldwide. CMV is also a serious cause of human disease in congenital infection and in infection of individuals with abnormal immunity. For example, CNW is a common and serious cause of disease in individuals with HIV infection. Because of its ability to cause disease in these situations, there is currently intense interest in the ability of vaccines to prevent or modify the course of CMV infection. We have developed a murine model of vaccination to modify immunity to CNW infection. We will utilize this model to determine if acute or chronic ethanol consumption alters either the course of CMV infection or the host response to vaccination. The broad objective of this proposal is to test the hypothesis that ethanol consumption will alter the host response to vaccination. With this in mind, the specific aims of the proposal are the following: Specific Aim 1: To determine whether acute or chronic ethanol consumption alters the course of acute CMV infection. Specific Aim 2: To determine if acute or chronic ethanol consumption alters the ability vaccination to alter the host response for MCNW. The proposed experiments are designed to explore the effects of ethanol consumption on acute viral infection and response to vaccination in a highly defined and reproducible system. These studies will set the stage for a systematic analysis of the mechanisms by which ethanol alters the host responses to viral infection and viral vaccine administration.